Method of lowering ice-buckled cold room floors



July 24, 1951 A. w. RUFF 'A 2,561,676 I METHOD 0F LOWERING ICE-BUCKLE!) COLD ROOM FLOORS Filed Jan. l2, 1950 Cittorneg room out of service.

Patented July 24, l1951 Y .tionV of Pennsylvania 4V2.,561,(jl76'I Y o METHOD OF LOWERINGLIGErBUCKLED Y .COLD ROOMaELQORS v y `Alumni-W. Ruff, York, Pag-assignontoiV.::C.z-Pat yterson & -,Associates, Inc.,dYork, ln.,'fa;corpora `ApplicationJanuary 12, 1i9'50glSerialNoLI38311Z iefolims. (or. rc1-fas) This inventionfrelatesto refrigerated'.coldistor-L y age .orfreezing rooms having ytheir floors built directly onthe -ground.- More particularly this invention pertains to a method of` lowering.. such floors which have buckledupwardlmfdue vto the formation of ice inthesubjacent `earth,without .entirely tearing up and replacing .thefloor.

.The floors of cold storage rooms which are '..built directly on the ground ordinarily consist of .upper and lower layers of concrete separated A.by a layer of thermal insulationmaterial, usual- `ly cork. Even though such iioor is insulated, there is a transfer of heat therethrough from the ground immediately adjacent theunderside vof the lower concrete slab into the room.' The.

earth, which isV usually `a fairly good. heat in- ,sulaton resists the flowof heat from lower elevations to replace this heat loss( Hence, the earth under the floor gradually chills and, in time, v`reaches freezing temperature.

inthe earth begins to freeze and form ice. Such 'formation is effected in strata-likelayers separated by thin layers of earth. "Experience indicates that such ice, once formed, doesnot melt unless the :door is warmed up'for some "time, These ice accumulations have a highly destructive effect because of the expansion whichtakes place 'during their formation. "It often takes several years for enough ice toaccumulateto cause visible damage, but experience'has proved thatthe formation of such ice creates a force Vthat raises and eventually" buckles or ruptures the `floor. This is particularly true of large rooms. Cases have been observed where the floors buckled upto 12 inches, even though a few inches is usually serious yenough to put a cold In a fewv known instances ,the entire building structure was shatteredfby such ice formation. s

` `Preventive measures are known. Suchfmeaso .ures include the casting of warming pipesin the .lower floor-slab, and constructing the floor with .an air space between theiioor and the subjacent earth. These preventive measures, while .effective, can be incorporated only on new construction and cannot easily be employed tovjcorrect thesituation once it develops. Prior to this'invention the only known method of coping with :an kice-buckled oor was to ,tear up theeentire iloor, thus sufliciently damaging the expensive cork insulation to render it unt for further use, and to re'lay the entire floor. Such procedure is a time consumingand costly. operation, sometimesamounting to as high as $4.00 per square foot of `floor area.

Accordingly, it is an objectof'this vinvention to provide -a simple, and inexpensive-method, involving a minimum of time,.and labor, for vlower- '2.20 `Once freezing temperature is reached moisture ..a..refrigerated roomthat has buckled upwardly .duevto the v.accumulation of .ice in thesubjacent learth'.

It `is a. further objectof this inventiontoprovideesuch .a method that will .also prevent 'the further accumulation of ice.

`Other. objectsand advantages of the invention .will be. evidentfrom thefollowing description and accompanying drawing in which .Figure 1 is a fragmentary view, in vertical sec- `tion, 'of va .refrigerated .room` having a groundlaid `floor thathas'been buckled' by -the'formation lof ice Tin thev subjacent earth.

Y.Figure 2 .is an enlarged vfragmentary view'ofv a `portion of v.Figure "1 illustrating the method ,of

loweri'ngthebuckled "floor in accordance with ,this invention.

j Figure 3`is a view corresponding"to"'FigureT2 Iillustrating the'lowerediloor upon completion'of the .method of this' invention.

Referring nowto Figure'l, there is lshown a 'portion of refrigerated room l'havinga side wall Il resting upon a concrete foundation 'I2 and provided with'interior insulation `I3. `The wall"|'| may be of any'suitable constructionA material, Such-as concrete,'wood, brick, cinder block,

etc. The insulation l'3 lpreferably is cork, al-

rthough other appropriatetthermal linsulating ma teriafl` can "'be' used.

The floor of the room, which'islai'd Y'directly jupon'theground"I'4,"preferably consists of upper "an'djlower 'slabs of Yconcrete 'I5 and I'6,' respectively,'separate'dbya layer of thermal insulation 'l`l,gpreferably'cork. "The'lower slab IB servesas a.' foundation for' both the' insulation FI and the upper slab "f5, whichlatter'is the wactual 'floor .of 'the room l0. lContinuous low 'temperaturesin Hence, this buckledarea vf the 'floor iis -no "longer useful. Additionally, vthe break 20 in the cork vinsulation permits a more rapidtransfer of heat "fromthefsubjacent earth H to the room |10, soithat ice accumulation is accelerated with consequent increase in the rate of `damage to the iloor.

.In order to' lower the buckled area of theffioor in accordance with this invention, a pit .or hole 2| is sunk through the criticalpointin the r'floor and'into the frozen ground I4 therebeneath, as .shown in `Figure'2. "This pit. 2l is of a ,size suf- "iicient to enable apparatus, subsequently .de-

scribed, to be.,easi1y manipulated therein. `A pit .3 )to ,4.jfeetfsquare and deep enough `to extend .3 or '4feetbelow1 the normal level Yof the lower slab j VIltis usually 1 adequate.

ring and Asettling the earth-,laid concrete .floor of A601:'- ffIThe nekt step consists .of forcing or drivingfa.

in the pit 2|.

plurality of sectional conduits horizontally outwardly through the side walls of the pit 2| into the frozen ground beneath the floor. The conduits are arranged to radiate from the pit in order to cover the entire affected area. Each conduit consists of a pointed nose section 22 and a plurality of additional sections 23 adapted to be` threadedly or otherwise suitably coupled together. After the nose section 22 has been driven into the earth the next section 23 is coupled on and the two sections driven further into the earth. Additional sections 23 are successively connected to the conduit and the latter driven farther into the earth until the nose section 22 substantially reachesl the periphery ofthe iced area.

` The purpose of these conduits is to carry electric heating cables 24. One end of each cableis secured in the nose section 22 and the cable strung through the remaining sections 23 of each conduit before the latter are successively joined together.

The conduits ma-y be driven or forced into the frozen earth by any suitable means. One practical means is a hydraulic jack (the cylinder of which is shown at 25), preferably of ten tons or larger rating, which is appropriately blocked, as at 26, and shored, as at 2l, in operating position In order to prevent damage to the heating cable during the operation of the jack cylinder 25 a pressure head 28, which is slotted, as at 29, to pass the cable 24, is used between the conduit and the jack plunger 3|). The jack hydraulic pump (not shown) may be made as a unit with the cylinder 25 or be a separate mechanism adapted to be positioned out of the pit and connected to the cylinder by appropriate hydraulic lines.

If the ground is frozen so hard that it is impracticable to force or drive the conduits thereinto, lateral holes may be bored or drilled in the side walls of the pit by means of suitable earth drilling apparatus (not shown). The conduits may then be inserted in place in such holes with little difculty.

After all the conduits have been forced into place, the cables 24 are connected with a suitable source of electric power (not shown) by a power connection (not shown) that leads out of the pit. The pit may then be filled up with earth to about the level of the conduits (as shown in Fig. 3). Thermal insulating material, such as rock wool blankets 3|, is used to ll the remainder of the pit. Current is then supplied to the cables 24 to warm the conduits and melt the layers of ice I8. As the ice melts, the floor will gradually lower under its own weight. A period of about one month, or even longer, may be necessary to completely melt the ice and dry the earth sufficiently to permit the floor to settle back to its original position shown in Figure 3. Because of the pit insulation 3|, however, the room may be` placed in service during such period.

After the floor has settled completely, an angle frame 32 may be fitted in the mouth of the pit to receive a wooden pit cover 33. The pit insula-` tion 3|' is left in place as a replacement for dis-I carded cork insulation. Any large cracks remaining in the floor after it has settled completely preferably are sealed with a suitable caulking: compound.

To prevent a recurrence of ice formation when.

' the room is back in service, current is reapplied as needed to the heating cables. A suitabley `thermostatic control for such current is the most convenient means" of preventing the temperature ,into many small pieces.

of the subjacent earth from again lowering` td freezing. An earth temperature of the order f 40 F. is usually practical from the standpoint of power consumption.

Preferably the repair of buckled floors by this kmethod is initiated before the floors have been spirit and scope of the following claims.

I claim:

1. The method of lowering the earth-laid floo of a refrigerated room, which iioor has been buckled upwardly by the formation of ice accumulations in the subjacent earth, the steps comprising; sinking a pit into the earth adjacent the buckled area of the floor; disposing heating conduits substantially horizontally through at least one sidewall of said pit into the iced earth beneath said buckled area; and supplying heat to said conduits for a period sufficient to melt the ice accumulations and dry the earth beneath said buckled area to thereby permit the buckled floor to settle back to normal position under its own weight.

2. The method defined in claim 1 including theadditional step of preventing the reformation of ice accumulations, once they have melted and after the room is back in service, by continuing to supply heat to the heating conduits sufficiently to maintain an above-freezing temperature of the subjacent earth.

3. The method defined in claim 1 in which heat is supplied to the conduits electrically and locally.

4. The method defined in claim 1 in which the disposing step is accomplished by forcing the heating conduits into the iced earth.

5. The method defined in claim l in which the disposing step is accomplished by boring lateral holes into the sidewall of the pit and inserting heating conduits into said holes.

6. The method of lowering the earth-laid concrete floor of a refrigerated room, which floor has been buckled upwardly by the formation of ice accumulations in the subjacent earth, the steps comprising; excavating a pit, adjacent the buckled oor area, through the floor and into the subjacent frozen earth; disposing elongated electrical heater means substantially horizontally through the sidewalls of said pit into the iced earth; supplying electric current to said heater means for a period sufficient to melt the ice accumulations and dry the earth beneath said buckled area to thereby permit the buckled floor to settle back to normal position under its own weight; filling said pit with thermal insulating material in at least the upper portion thereof: and covering said pit with rigid material.

ALONZO W'. RUFF.

REFERENCES CITED UNITED STATES PATENTS Name Date Cooper Feb. 18, 1908 Number 

